automated eBay price tracking

Hello everyone. I’m new to the forum and recently got back into collecting earlier this year. I’m wondering what resources are available for tracking card prices.

I signed up for an eBay developer account and have been playing around with their APIs. I was able to write some code to quickly grab price info for recently sold PSA 9 1st edition holos and organize this into a google sheet (see link below). I feel this could be useful for both determining card price and tracking price over the years. You could potentially scale this up and grab data for every card and every grade and format everything nicely on a webpage. Does this currently exist? What do you guys think?


It’s not an easy problem to tackle. Take a look at your data and you’ll see why. The basic problem comes down to the fact that parsing a listing’s title is not a reliable way of categorizing the listing. For your 1st edition search queries, you have Chinese, German, Unlimited, entire sets, etc in there that make your sorted data worthless. To do this with automation, you’d need to create a machine learning classifier that could handle hundreds of thousands of categories due to the insane number of qualifiers (Language, 1st/Unlimited, PSA/BGS, seller-reported condition, set, number) for each card. The amount of training data that classifier would need to start getting good results would be astronomical, and you’d need to do the labeling by hand for a lot of it. I personally don’t see any way to do a project like this with consistent, accurate automation.

eBay recently bought Terapeak which was a company focused around providing more in depth price tracking and search functions to a longer period of eBay sale history. It will be interesting to see what they do with that.

Let’s do it boys. I’m warming up the recurrent neural networks as I’m typing this.

Yes, I agree it’s a difficult problem since the titles have so much variation. I can see my Charizard search only returns 3/10 correct items and I only know that because I’m familiar with the current price range. There’s definitely a lot of work required to make the results accurate. I’m wondering if we had people both interested in automated classification and manually confirming sales, whether or not we could make a useful price tracking tool.

For comparison, there is for tracking prices of vinyl records.